Conventionally, as the method for manufacturing a multilayer printed board, for example, the patent documents 1 and 2 disclose a method for manufacturing a multilayer board.
The patent document 1 discloses a method for manufacturing a multilayer board having electrodes on both sides of the board by manufacturing a plurality of interlayer connected double-sided boards and stacking these double-sided boards via a film insulator that is processed to be capable of interlayer connection.
The patent document 2 discloses a method for manufacturing a multilayer board having electrodes on both sides by depositing a single-sided conductor pattern film that is a resin film with a conductor pattern on a single side thereof and removing the resin film to expose the electrodes. The patent document 2 also discloses a technique of removing a single-sided conductor pattern film that is a multilayer board surface, forming a bottomed via hole with the conductor pattern as a bottom surface and filling the bottomed via hole with a conductive paste thereby to achieve conduction of conductor patterns of such single-sided conductor pattern films adjacent to each other via this conductive paste. This structure makes it possible to bring the conductor pattern layers of the multilayer board into conduction via the conductive paste in the via holes.    Patent document 1: Japanese Patent Application Laid-Open No. 2000-38464 (Patent No. 3355142)    Patent document 2: Japanese Patent Application Laid-Open No. 2003-86948 (Patent No. 3407737)